1. Field of the Invention
The present invention relates to a storage unit and a circuit for shaping a communication signal.
2. Description of the Related Art
With a progress of information technologies in the recent years, a communication speed has increased at which data is input to and output from a disk drive of a storage unit. For example, in the case of data input/output that complies with, for example, the fiber channel standards, communication speeds of 1 Gbps (Giga bits per second) and 2 Gbps are put to practical use in communication presently. Further, technologies for communication at a communication speed of 4 Gbps are under development for practical utilization.
Thus, there are prevailing disk drives having various communication speeds in a market.
By the way, there are some cases where it is desired to use disk drives having different communication speeds in the same storage unit as in the case of, for example, providing an additional disk drive to a storage unit that is in service.
However, a conventional storage unit does not have such a mechanism that disk drives having different communication speeds at which data is input/output are used in a mixed manner and so cannot accommodate needs of a user who wishes to use disk drives having different communication speeds as mixed in the same storage unit.